pcb Driving 10x10 LED matrix with AVR

Designing a controller PCB for a 10x10 white LED matrix clock (inspired by the tutorial here ). It`s based off an ATmega328 AVR IC and Maxim DS3234 SPI RTC. However, I`m stuck: I have no idea how to control my custom non-standard 10x10 LED matrix. Originally I was going to use a Maxim MAX7219/7221 IC, but it can only drive 8x8 LED matrices. Then I was looking at some sort of charlieplexing solution with a